1. Field of the Invention
The present invention relates to an electrophoretic display device and a method of manufacturing such an electrophoretic display device. More particularly, the invention relates to such a device having low power consumption and a method of manufacturing the same.
2. Description of the Related Art
Recently display devices using electrophoresis have been proposed. One such electrophoretic display device disclosed in Japanese Patent Application Publication No. 2003-216111 includes a viewing surface and an undersurface, with upper electrodes provided on the viewing surface and lower electrodes on the undersurface. Microcapsules are provided between the viewing surface and undersurface as image displaying means. Colored particles of different colors are dispersed in the microcapsules, the particles being charged with a positive or negative polarity depending on their color. When a voltage is applied across the upper and lower electrodes, an electric field is generated therebetween, causing the charged particles to migrate in the microcapsule. The migration of these colored particles is used for displaying images on the viewing surface.
The display device disclosed in Japanese Patent Application Publication No. 2003-216111 uses microcapsules having shells that encapsulate the particles. These shells are relatively thick (4 μm) with respect to the outer diameter (30 to 100 μm) of the microcapsules. As a result, the contrast of an image formed by two types of colored particles cannot be reproduced due to the thickness of the shell.
Further, a long distance between the upper and lower electrodes requires a high voltage for migrating the colored particles in the microcapsule. Hence, this type of display device tends to consume more power than the display devices with a reduced thickness.